Refrigerating apparatus



Filed Feb 26 2 Sheet eet l Gno Oct. 15, 1929.

' J. G. KING REFRIGERATING APPARATUS Filed Feb. 6, 1926 2 SheetsSheet 2 6cm we l atented Oct. 15, 1929 duced, thus maintaining a UNITED STATES PATENT OFFICE JESSE G. KING, OF

DAYTON, OHIO, ASSIGNOB, BY IESN E ASSIGNMENTS, '10 FBIGIDAIBE- CORPORATION, CORPORATION OF DELAWARE I BEFRIGEBATING APPARATUS Application filed February 6, 1926. Serial No. 88,588.

This invention relates to cooling units for mechanical refrigerators. 4

it is among the objects of the present in- -vention to provide a cooling unit which, when installed in a refrigerator cabinet, will cool the cabinet to the desired low temperature,

'not too cold for general refrigeration, and

tively large heat absorbing surfaces and proride for the conduction of heat from spaced points of the surfaces so that the temperature gradient between the parts thereof is remore nearly uniform temperature difference between the parts of. the heat absorbing surface and the circulating medium to be cooled thereby.

l urthermore, the inventioncontemplates the provision of a freezing zone, in which water or other substances may be chilled or frozen, which zone is shielded from the warming action of the circulating medium by the heat absorbing surfaces for causing quick chilling or freezing within the zone, and which surfaces are utilized also for accelerating the cooling of the freezing zone.

in carrying out these objects, I provide relatively wide metal fins attached to the cooling ducts of the cooling unit thereby greatly increasing the effective cooling surface of the unit. The width of the fins is preferably such that during normal operation frost will not build up on the fins to the outermost edges thereof. Hence part of the tin surface is always freely exposed to the circulating air and this causes rapid defrosting of the fins back toward the cooling d ucts during the idle period of the refrigerant compressor. Obviously any decrease in the accunu'ilation of frost on the outside of the cooling unit by such means increases the efiiciency of the "unit since a layer of frost ant conveying ducts.

materially impedes the flow of heat toward flattened ducts whereby the quantity of.

refrigerant is decreased and the spacing of the ducts is increased-without decreasing the cooling area the'reof, thus permitting a better circulation of air therebetween and a better heat transfer relationship between the ducts and the air. Also the flattening of the ducts at the points where the fins are attached thereto enables abetter thermal bond to be made between the fin and the duct.

Another feature of the invention is the construction and arrangement of the refriger- In the specific embodi'rnent, I provide two shapes of duct loops, saidf loops being alternately arranged and reversely turned when assembled to the header so that the vertical legs of, the loops fall in three spaced vertical planes on each side of theheader, thereby giving a better heat transfer between the ducts and the circulating air cooled thereby. This feature reduces cost of manufacture since all the loops are bent up to only two shapes, and also provides the proper distribution of ducts to form a freezing zone, and insures desirable temperatures of the cooling unit used primari'ly' for cooling the circulating air flowing thereover.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein preferred forms ofembodiments of the present invention are clearly shown.

In the drawings:

' Fig. l is a front elevation of a cooling unit a cooling unit built according to this invention located therein.

In the drawings, similar reference characters refer to similar parts throughout the several views. I

Referring first to Figures 1 and 2, numeral 10 designates the cylindrical header or tank which contains a suitable form of float valve (not shown) for maintaining the liquid refrigerant within tank 10 at a substantially constant level. Liquid refrigerant is led to tank 10 through the duct 11. The vaporized refrigerant is led from said tank through the duct 12 which leads off from the space above the liquid level in tank 10.

A series of duct loops 15 and 16 are connected in parallel to tank 10 below the liquid level therein and depend therebelow into the air or medium cooled by said cooling unit. The wide loops 15 each has a vertical duct leg 15 depending downward adjacent the vertical axis of the tank 10 and a second vertical leg duct 15 which is offset laterally a considerable distance from said axis of the tank 10. Similarly the narrow loops 16 each has a vertical duct leg 16 longitudinally aligned with the legs 15', and a second vertical duct'leg 16" which is offset laterally about half asmuch as the leg 15. All the loops 1'5 are bent up to the same shape but when they are assembled to the header 10' alternate loops are turned reversely so that the offset legs 15" project alternately on op-' posite'sides of the header. Similarly all the loops 16' are bent up to the same shape and alternate loops turned reversely when assembled to the header 10. Preferably the wideand narrow 100 s are interspersed, and in the form illustrate two narrow loops alternate with two wide loops. Fig. 2 clearly shows the arrangement of the wide loops 15 and the narrow loops 16. Byvirtue of the construction shown and described, three sets of ducts are provided on'each side of the header or tank 10, namely the set provided by legs 15' and 16', the set rovided by legs 16" and the set provided by legs 15". The sets of ducts 1'5 and 16 on opposite sides of the sleeves or ice-tra sup orts 25 provide a compartment there or w il e the sets of ducts 15" are spaced at a greater distance from the compartment than the ducts 16". The loops are preferabl arranged in sets, each set including a wi e loop 15 and a narrow loop 16. The legs of the loops are flattened to decrease the refrigerant capacity thereof without decreasing the heat absorbing outer surface resented to the medium to be cooled. Prefera ly the ducts are flattened in a plane transverse to the directionof movement of the circulating air or medium to be cooled thereby so as to present an edge to the moving air so that the circulation of the air is not impeded while presenting a wide'heat absorbing surface disposed longitudinally in nearest adjacent vertical legs 15' or 16, as

the case may be. Thus each fin has a plurality of refrigerant conveying ducts thermally connected therewith at spaced apart points on opposite sides thereof so as to reduce the temperature gradient between the parts thereof, thereby providing a more effective temperature difference between the parts thereof and the medium to be cooled thereby. By this arrangement a plurality of groups of fins are provided, the groups being disposed laterally of one another and on opposite sides of the header 10; and the fins of one group are interposed between the planes of the fins of the other group. The loops 16 are interposed between the planes of the fins 20 and assist in cooling the circulating medium passing through thechannels formed by the fins. The loop legs 16 extend a different distance from the header than other legs of the loop and therefore the possibility of frost bridging the duct legs is minimized. These legs 15' and 16 are preferably, slightly bent to lie up close against the fins 20 before being soldered thereto in order to avoid excessive bending the fins 20 to bring them in contact with said legs.

The sheet metal copper plates or fins 20 together with the metallic duct loops'15 and cast metal or other non-manipulative metal.

The ice tray sleeves 25 are soldered to the vertical legs 15' and 16', and are thus thermal- ;ly connected through the fins 20 to the legs 15". It will be noted that each of the loops 15' and 16 has only one leg adjacent the sleeves 25, the other leg being offset laterally out into the air. Therefore when the sleeves 25 for the freezing trays 26 are being soldered in place each loop is flexed laterally as a whole until the inner legs 15' or'16' contact with said sleeves 25, thus accurately, aligning all the inner legs regardless of whether or not their corresponding outer legs are thereby accurately aligned. Each of the sleeves 25 is adapted to contain a removable 'ice tray 26 which is maintained at a freezing tempera.- ture by the cooling unit.

Preferablythe wide loops :15 areheld in In the normal operation of this cooling unit the refrigerant in the legs 15' and 16 absorb heat chiefly from the freezing trays 26 when water is contained within the same, and since they are not greatly exposed to the circulating air or medium, they soon have a layer of frost built up on their outer surface.

The offset legs 15 and 16 however project out into the circulating air and hence serve principally to cool said air. The legs 15 and 16 as well as the fins 20 are arranged substantially coextensive along the length of the cooling units. Thus the enclosure or compartment, which is formed by the legs 15 and 16' is nested between the legs 15" and 16 and fins 20, may be termed a freezing zone and this zone is thereby shielded throughout its entire length from the warming action of the circulating air. In this manner quick freezing is insured while desired temperatures for the general refrigeration of the refrigerator cabinet are obtained. The fins 20 greatlyincrease the effective cooling surface of the wide loops 15 and hence greatly reduce or entirely prevent the accumulation of frost on the exterior of the legs 15". By greatly increasing the effective cooling surface and also limiting or preventing the accumulation of frost more efficient heat transfer is obtained and hence the length of time of operation of the compressor unit which supplies liquid refrigerant to the cooling unit is reduced.

Under certain operating conditions the legs 15 of the loop 15, although. spaced from the freezing zone, accelerate the chilling of the freezing zone. This is particularly true when warm water to be frozen or delicacies to be chilled are pla. id in the trays. In these circumstances heat will be conducted outwardly from the freezing zone by the fins 20. Since these fins are connected with the outwardly disposed duct leg 15" and with the ice tray sleeves, they establish a heat exchange relationship between the freezing zone and said legs'at a plurality of points along the length of the zone, and thus said legs accelerate the chilling and freezing of substances within the zone.

Figs. 3, 4, and 5 illustrate a modification of the cooling unit of Figs. 1 and 2 described above,wl1erein the wide copper fins have been omitted. This form may be preferred under certain conditions, for instance when less cooling capacity is required and the compartment for the cooling unit. is not sufficiently large to permit the use of the fins. In this modified form the same reference characters are used in the drawings to designate the same parts which are described in detail in the above description. Though no fins are present the legs 15 and 16 project out into the circulating air in order to better absorb the heat therefrom. If the legs 15 and 16" become coated with frost to a considerable thickness good circulation of air is still obtained since the legs 15 are not aligned with the legs 16", and hence there is no possibility vof frost bridging across between these legs and thus stopping proper air circulation through the cooling unit.

Fig. 6 illustrates the coolingunit of Figs. 3, 4 and5 installed in a display case for the purpose of showing one arrangement with the food compartments cooled thereby. The

arrows indicate the general circulation of air over the cooling unit and thence through the food compartments.

It is quite apparent that the central part of the cooling unit is colder than the outer parts, particularly when the water is frozen or no water is-contained within the ice trays. The air passing between the fins will maintain the outwardly extendinglegs warmer than the inner legs, particularly, the. fins maintain the legs 15" at 'a higher temperature than the legs 15. This arrangement causes a thermally non-symmetrical relation of the branches of the loops, and therefore a thermally non-symmetrical relation of the loops with respect to the plane of the vertical axis ofthe header and the refrigerant.

will boilmore violently in more outwardly extending legs than in the inner legs. Consequently, iore gas and less liquid will be present in the former legs than in the latter. This difference of apparent density of re frigerant in the vertical parts of the opposed legs or branches will create unbalanced columns of refrigerant to cause what may be termed a prevalent flow of refrigerant downwardly from the header, through the branches adjacent the vertical axis of the header,

through the horizontal cross legs, whence the refrigerant gas will flow upwardly through the opposed vertical branches to the header. By establishig a prevalent flow, as above described, in contradistinction to a circuit in which the liquid flows in one direction and vapor in the opposite direction,

the upward flow of vaporized refrigerant in oneof the opposed branches in which the vaporization is greater, the gaseous refrigerant can escape more readily because its upward movement isnot impeded by the movement of the downwardly flowing liquid refrigerant. Thusby my arrangement, I provide a circuit in which the vaporized refrigerant readily flows therefrom and is immediately replaced by liquid refrigerant to thus improve the thermal efficiency of the circuit.

While the forms of embodiment of the present invention as herein disclosed, ponstitute preferred forms, it is to be understood that other forms might be adopted, all coming Within the scope of the claims which fol- What is claimed is as follows:

1. A cooling unit for mechanical refrigerators comprisin a header,a series of duct loops depending from said header and connected thereto in parallel, said loops each having two substantially upright legs, and a metal fin attached to only one upright leg. of certain of said loops.

2. A cooling unit for mechanical refrigerators comprising: a header, a series of duct loops depending from. said header and connected thereto in parallel, said loops each having one upright leg depending downward adjacent said header and a second upright leg offset laterally from said header, and metal fins attached to certain of said lateral-- ly-offset legs.

3. A'cooling unit for mechanical refrigerators comprlsingz an elongated header, a

. series of duct loops depending from said header and connected thereto in parallel along the length of said header, said loops having a uniform depth but varying width and having a staggered relation of the upright portions of said loops.

4. A cooling unit for mechanical ref'rig-. erators comprising: a header, a series of duct loops depending from said header and connected thereto in parallel, said loopseach having two substantially upright legs and a horizontal leg, said horizontal legs lying in one plane and each of said upright legs lying in one of three spaced vertical planes on each side of said header.

5. A cooling unitfor mechanical refrigerators comprising: a header, a series of duct loops depending from said header and connected thereto in parallel, a freezing compartment formed by said ducts, each loop having one upright leg adjacent said compartment and a second upright legs aced y from said chamber, said spaced legs eing spaced at varying distances from said compartment whereby saidloops permit abetter circulation of air therethrough.

6. A cooling unit for mechanical refrigerators comprising: a plurality of sets of loops each including a pair of legs lying substantially in a vertical plane, one leg of each loop co-operating with the corresponding leg of the other loop to form a compartment for 'an ice-making receptacle, and-the other leg of each loop extending beyond the compartment, said other legs in different sets of loops extending different distances from the compartment. Y

7. A cooling unit for mechanical refrigerators comprising: a plurality of ducts, certain of said ducts forming a compartment for an ice-making receptacle and the other of said tors comprising, conduitmeans for circulating refrigerant arranged to provide a space adapted to receive an ice-making receptacle, a support for an ice-making receptacle within the space and spaced from a portion of said conduit means, and metallic heat conducting means bridging said space between the conduit means and the support and connected to the latter at a plurality of points along the length thereof.

9. A cooling unit for mechanical refrigerators comprising, conduit means for circulating refrigerant arranged to provide a space adapted to receive an ice-making receptacle, a support for an ice-making receptacle within the space and spaced from a portion of said conduit means, and heat conducting means in intimate thermal contact with said support and said portion, said heat conducting means including aplurality of portions spaced from one another to permit the circulation of air between same.

- 10. A cooling unit for mechanical refrigerators comprising, conduit means for circulating refrigerant arranged to provide a space adapted to receive an ice-making'receptacle, a support for an ice-making receptacle withinthe space and spaced from a portion of said conduit means, and vertical heat conducting fins in intimate thermal contactwith said support and said portion.

11. A cooling unit adapted to be placed in the path of a cooling medium flowing there-' over for cooling such medium, said cooling unit comprising a plurality of fins spaced from one another and in intimate thermal contact with a refrigerant, and refrigerant conveyin ducts spaced from the fins and disposed etween the planes of the fins.

12. A coolingunit adapted to be placed in the path of a cooling ine ium flowing there- .over for cooling .such medium, said cooling unit com rising a plurality of ducts, a plurality of 115, certain of said ducts being each thermally connected with a fin and certain other of said ducts being without fins, said latter duct-s being interposed between the finned ducts. I

13. A cooling unit adapted to be placed in the path of a cooling medium flowing thereover for cooling such'medium, said cooling unit comprising a plurality of ducts, a plurality of fins, certain of said ducts being each thermally connected with a fin and certain other of said ducts being without fins, said first mentioned ducts extending outwardly beyond the ducts without fins, and said ducts without fins being interposed between the finned ducts.

14. A cooling unit adapted to be placed in the path of a coolin medium flowing thereover for cooling suc medium, said cooling unit comprising a plurality of duct loops having varying widths, the upright legs being arranged in rows and the legs of one row bein staggered with respect to the legs of anot er row.

15. A cooling unit adapted to be placed in the path of a cooling medium flowing thereover, saidcooling unit comprising a plurality of ducts, certain of said ducts being arranged to form a compartment for an icemaking receptacle and other of said ducts flankin said compartment,'certain of said latter ucts bein spaced closer to the compartment than 0t er of said latter ducts and oflset rearwardlyctherefrom.

16. A cooling unit adapted to be placed inthe path of a cooling medium flowing thereover for cooling such medium, said cooling unit comprising duct means providing a freezing zone for an elongated ice tray, means for shielding the freezing zone from the warming action of the circulating medium, said means comprising spaced fins disposed along substantially the entire length of the freezing zone outwardly thereof and duct means thermally connected with said fins.

17. A cooling unit adapted to be placed in the path of a cooling medium flowing thereover for cooling such medium, said cooling unit comprising a plurality bf upright duct means, certain of said ductmeans being spaced apart to provide therebetweena compartment adapted to receive an elongated ice tray, metallic fins hermetically united with and extending laterally from said duct means along substantially the entire length of said compartment.

18. A cooling unit adapted to be placed in .the path of a cooling medium flowing thereover for cooling such medium, said cooling unit comprising a plurality of upright duct means, certain of said duct means being spaced from and positioned on either side of a freezing compartment, a support for an ice tray located within said compartment and spaced from the aforesaid certain duct means, and metallic fin means connected .to said support at a plurality of points along the length thereof and bridging the space between said support and the aforesaid certain duct means whereby to establish heat conducting relationship between said parts.

19. A cooling unit adapted to be placed in the path of a cooling'medium-flowing thereover for cooling such. medium, said cooling 'unit comprising duct means providin a freezing zone for an elongated ice tray, uct means spaced outwardly from the freezing zone, and fin means establishing a thermal heat transfer relationship between said outer spaced duct means and the freezing zone at a plurality of points along substantially the entire length 0 the latter;

20. A cooling unit adapted to be placed in the path of a cooling medium flowing there- 'over for cooling such medium, said cooling unit comprising duct means providin a freezing zone for an elongated ice tray, uct means spaced outwardly from the freezing zone, and fin means establishing a thermal heat transfer relationship between said outer with a refrigerant and with said medium to be cooled, said portion being arranged to pro Vide a compartment adapted to receive an ice making receptacle and comprising a series of spaced apart flattened duct channels disposed alongside one another for conveying refrigerant therein, and means for connecting the walls of adjacent duct channels to provide a continuous metallic wall facing said compartment.

22. In a refrigerating apparatus, a cooling unit adapted to be placed in the path of a cooling medium flowing thereover for cooling such medium, said cooling unit comprising a wrought metal portion in intimatecontact with a refrigerant and with said medium to.

be cooled, said wrought metal portion provi-ding a compartment for an ice making receptacle and itself constructed and arranged to provide a series of spaced apart flattened v duct channels for conveying the refrigerant therein.

23. In a refrigerating apparatus, a cooling unit adapted to be laced in the path of a cooling medium flowing thereover for cooling such medium, said cooling unit comprising heat exchange means in intimate contact with a refrigerant and with said medium to be cooled, said heat exchange means having a wrought metal portion providing a compartment for an ice making receptacle and itself constructed and arranged to provide a series of fiattenedduct channels for conveying the refrigerant therein, said flattened duct channels being arranged with their long transverse axes substantially parallel to one another.

24. A refrigerating apparatus comprising a cooling unit adapted to be placed in a path of a cooling medium flowing thereover for cooling such medium, said cooling unit comprising a series of ducts, said ducts having portions spaced from one another and flattened in a direction transverse to the flow -of.

cooling such medium, said cooling unit comprising a series of ducts, said ducts having portions spaced from one another and flattened and'presenting an edge to said medium flowing thereover, and means for maintaining a quantity of volatile refrigerant in said ducts.

26. Refrigerating apparatus comprisinga cooling unit including refrigerant conveym duct means, said duct means being flattened: said ducts being adapted to contain a qualitity of volatile refrigerant, and fin means sebeing flattened and arranged with their long transverse axes substantiall parallel to one another,said ducts being a apted to contain a qpantity of volatile refrigerant, and fin means lying substantially parallel with said axes of a plurality of ducts and thermally connected with said ducts.

V 29. A'cooling unit adapted toloe placed in the path of a cooling medium flowing thereover for cooling such medium, said cooling unit including a heat absorbing plate or fin and refrigerant conduit means for cooling said plate, said conduit means including or! tions spaced from one another alon the p ate, one of said portions being thermaly connect ed to one side off the plate and another of said portions being thermally connected to the opposite side of the plate.

30. cooling unit adapted to he placed in the path of cooling medium flowing thereover for cooling such medium, said cooling unit including a plurality of heat ahsorhing plates or fins spaced from'one another to provide cooling medium path between same, and refrigerant conduit means for cooling saidplates, said conduit means being arranged in sets, said sets being each adapted to cool one of the plates and each set including portions spaced from one another along the plate, one of said portions heing thermally connected to one side of the plate and another of said portions losing thermally connected to the oppositeside of the plate.

31. A cooling unit adapted to he placed in the path of cooling medium flowing thereover for cooling such medium, said cooling unit comprising a header, a plurality of duct loo s connected with the header, certain of said duct loops each having a downwardly extending leg arranged relatively near the vertical ing leg relatively more remote from said axis,

and a plurality of fins, certain of said fins hes over for cooling such medium, said cooling 1 unit comprising a header, a plurality vof duc t loops connected with the header, certain of said duct loops each having a downwardly extending leg arranged relatively near the vertical axis of theheader and a downwardly extending leg relatively more remote from said axis, and a plurality of groups of fins disaxis of the-header and a downwardly extendposed laterally of one another, said fins being each thermally connected with one of the first mentioned loop legs and one of the second mentioned loop le s. p

33. A cooling unit a a ted to be placed in the path of cooling me ium flowing thereover for cooling such medium, said cooling unit comprising a header, a pluralityof duct loops connected with the header certain of said duct loops each having a downwardly extending leg arranged relatively hear the 1 vertical axis of the header and a downwardly extending leg relatively said axis, said loops bemg arranged in sets, and a fin for each of certain of said sets, the

fin of a set being thermall connected withv one of the first mentioned 00 and with'one of the second legs of said set. 1

34. A cooling unit adapted to be placed in the path of circulating medium flowing therelegs of a set entioned loop more remote from over said cooling unit comprising a plurality of oflset with respect to another group and wi the individual fins therefof interposed hetween the planes of the fins of the other group, a plurality of refrigerant conveying ducts, certain of said ducts lying parallel alongside and thermally connected with certain fins, and certain of the ducts lying arallel alon side and thermally connects with other of said fins. v

35. A cooling unit adapted to he placed in the path of circulating medium flowing thereover, said cooling unit comprising a header, a plurality of ducts connected with the header a plurality of groups of fins offset laterally with respect to one another, certain of said ducts being thermally connected to the fins relatively near the vertical axis of the header and certain of said ducts being thermally connected to the finsrelatively groups of fins, one group being laterallg more remote fromthe vertical axis of the header. 4 N I 36. A cooling unit for a rerrigerator comprising a header, duct loops connected with ing a downwardly extending leg? 7 are are

. ly connected with the fins,

arranged relatively near the vertical axis of the header and a downwardly extending leg relatively more remote from the vertical axis of the header, and fin means interposed between and thermally connected with theloops of each set.

37. A cooling unit adapted to be placed in the path of a cooling medium flowing thereover for cooling such medium, said cooling unit comprising upright fins, and a series of upright refrigerantconveying ducts thermalsaid fins and ducts being substantially coextensive at the lower parts, and said ducts extending at least to the bottom edge of the fins and cooperating to provide a base for the cooling unit.

38, A cooling unit adapted to be placed in the path of a cooling medium flowingthereover for cooling such medium, said cooling unit comprising upright fins, and a series of refrigerant conveying ducts including upright branches and horizontally disposed branches said fins being thermally connected- With the upright branches and extending to the horizontal portion, the lower edge of said horizontal'branches extending at least to the bottom edge of the fins and cooperating to provide a base for the cooling unit.

39. A cooling unit adapted to be placed in the path of a cooling medium flowing thereover for cooling such medium, said cooling unit comprising upright fins, and a series of the header,

over for cooling such refrigerant conveying duct loops each including a plurality of upright branches and a horizontal branch connecting the lower ends of the upright branches, said fins being thermally connected to upright branches and extending to the horizontal branches, the lower edge of said horizontal branches extending at least to the bottom edge of the fins and cooperating toprovide a base for the cooling unit.

40. A cooling unit adapted to be placed in the path of cooling medium flowing thereover for cooling such medium, said cooling unit comprising aheader, duct means connected with the header, said duct means providing a refrigerant circuit having its ends connected with the header, fin means connected with the duct means, said fin means and duct means being arranged for causing one of the opposed branches of the circuit to be subjected to a larger heat exchange area than the other opposed branch.

41. A cooling unit adapted to be placed in thepath' of coolingmedium flowing theremedium, said cooling unit comprising a header, duct means connected with the header, said duct means providing a loop having its ends connected with fin means connected with the loop, said fin means and duct means being arranged for causing one of the opposed branches of the loop to be subjected to a larger heat exchange area than the other opposed branch.

42. A cooling unit adapted to be placed in the path of coolin medium flowing thereover for cooling sucli medium, said cooling unit comprising a header, duct means connected with the header, said duct means providing a refrigerant circuit having its ends connected with the header, one branch of said with the header, said duct means providing a loop having its ends connected with the header, one branch of said loop being disposed relatively near the vertical axis of the header and another branch of said loop being disposed relatively more remote from said axis of the header, and fin means thermally connected with the last named branch.

44. A cooling unit adapted to be placed in the path of cooling medium flowing thereover for cooling such medium, said cooling unit comprising a header, duct means connected with the header, said duct means providing a refrigerant circuit having its ends connected with the header, and fin means, said finmeans and duct means being thermally connected and cooperating to provide a thermally nonspect to the plane of the vertical axis of the header.

45. A cooling unit adapted to be placed in the path of cooling medium flowing thereover for cooling such medium, said cooling unit comprising a header, duct means connected with the header, said duct means a loop having the ends thereof connected with the header, and fin means, said fin means and duct means'being thermally connected and cooperating to provide a thermally nonsymmetrical relation of the loop with respect to the plane of the vertical axis of the header.

46. A cooling unit adapted to be placed in the path of cooling medium flowing thereover for cooling such medium, said cooling unit comprising a header, duct means connected with the header, said duct means providing a refrigerant circuit having its ends connected with the header, and fin means, said fin means and duct means being thermally connected and cooperating to provide a thermally non-symmetrical relation of the opposed branch portions of the circuit.

47. A cooling unit adapted to be placed in nected with the header, said duct means pro-,

viding a loop having the ends thereof consaid cooling unit P v n i &

nected with the header, and fin means, said fin means and duct means being thermally connected and cooperating to provide a thermally non-symmetrical relation of the opposed branch portions of the loop.

48. A cooling unit adapted to be placedin the path of a cooling medium flowing there over for cooling such medium, said cooling unit comprising a header, duct means connected with the header, said duct means providing a refrigerant circuit having its ends connected with the header and fin means thermally connected with the duct means, said circuit and fin means being arranged for causing the refrigerant in one of the opposed branches of the circuit to have a diflerent apparent density than the other opposed branch of the circuit. 4

49. A cooling unit adapted to be placed in the path of a cooling medium flowing thereover for cooling such medium, said cooling unit comprising 'a header, duct means connected with theheader, said duct means providing a loop havingthe ends thereof connected with the header and extending below the header, and fin means thermally connected with the loop, said loop and fin means being arranged for causing the refrigerant in one of the branches of the loop to have a different apparent density than the other opposed branch of said loop.

In testimony whereof I hereto ai'fix my signature.

JESSE e. KING.

eof 

